Take a conventional jet, and modify the engine, to have a ring of venturi nozzels connected to a water reservoir.
The engineers at Vigin can sort it out in the lab.. When at cruising altitude, you rturn on the water, and water drops are sucked into the exhaust. The boil, and do Molecular Nuclear Fusion
1 H2O+TU->He+O+E2+X-ray TU=turbulence – a jet today gives off X-rays while workling.
The jet will now reach hypersonic speed, and cross the Atlantic using ¼ of the ariation fuel. Mach 3.5 – nearly twice the speed of concorde.